What was found
(CAN) WHILE MAINTENANCE DEPARTMENT WAS CONDUCTING THE PHASE 4, 800 HOUR INSPECTION ON THIS B300C AIRCRAFT, THE BEARING IN THE RUDDER HORN ASSEMBLY WAS FOUND TO BE UNSERVICEABLE ,THE BEARING WAS CORRODED AND WORN CAUSING EXCESSIVE UP AND DOWN MOVEMENT OF THE RUDDER. UPON REMOVAL OF THE RUDDER HORN TO FACILITATE THE REPLACEMENT OF THE BEARING IT WAS DISCOVERED THAT THE BOLT WAS ALSO WORN AND DAMAGED.THE BEARING AND THE BOLT WERE REPLACED WITH SERVICEABLE UNITS.